/*
 *   The contents of this file are subject to the Mozilla Public License
 *   Version 1.1 (the "License"); you may not use this file except in
 *   compliance with the License. You may obtain a copy of the License at
 *   http://www.mozilla.org/MPL/
 *
 *   Software distributed under the License is distributed on an "AS IS"
 *   basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
 *   License for the specific language governing rights and limitations
 *   under the License.
 *
 *   The Original Code is Matra - the DTD Parser.
 *
 *   The Initial Developer of the Original Code is Conrad S Roche.
 *   Portions created by Conrad S Roche are Copyright (C) Conrad 
 *   S Roche. All Rights Reserved.
 *
 *   Alternatively, the contents of this file may be used under the terms
 *   of the GNU GENERAL PUBLIC LICENSE Version 2 or any later version
 *   (the  "[GPL] License"), in which case the
 *   provisions of GPL License are applicable instead of those
 *   above.  If you wish to allow use of your version of this file only
 *   under the terms of the GPL License and not to allow others to use
 *   your version of this file under the MPL, indicate your decision by
 *   deleting  the provisions above and replace  them with the notice and
 *   other provisions required by the GPL License.  If you do not delete
 *   the provisions above, a recipient may use your version of this file
 *   under either the MPL or the GPL License."
 *
 *   [NOTE: The text of this Exhibit A may differ slightly from the text of
 *   the notices in the Source Code files of the Original Code. You should
 *   use the text of this Exhibit A rather than the text found in the
 *   Original Code Source Code for Your Modifications.]
 *
 * Created: Conrad S Roche <derupe at users.sourceforge.net>,  25-Jul-2000
 */

package com.conradroche.matra.data;

import java.util.ArrayList;

/**
 * Class to read DTD data.
 * 
 * @author Conrad Roche
 */
public class DTDData extends ParseableData {

	/**
	 * DTDData constructor.
	 */
	public DTDData() {
		super();
	}
	/**
	 * DTDData constructor.
	 * 
	 * @param strData The data to be parsed.
	 */
	public DTDData(String strData) {
		super(strData);
	}

	/**
	 * Checks if the specified char follows
	 * the NameChar production of the XML Specification.
	 *  
	 * @param c The char to check.
	 * 
	 * @return <code>true</code> if this char is a 
	 * 		valid Name char; <code>false</code>
	 * 		otherwise.
	 */	
	private boolean isNameChar(char c) {
		
		//[4]    NameChar    ::=    Letter | Digit | '.' | '-' | '_' | ':' | CombiningChar | Extender 
	
		//CR: TODO: Check for CombiningChar and Extender
		if(Character.isLetter(c) || Character.isDigit(c) ||
			c == '.' || c == '-' || c == '_' || c == ':') {
				return true; 
		}
	
		return false;
	}
	
	/**
	 * Checks if the specified char is a valid
	 * first char for the Name production in 
	 * the XML Specification.
	 * 
	 * @param c The char to check.
	 * 
	 * @return <code>true</code> if this char is a 
	 * 		valid first char for a Name; 
	 * 		<code>false</code> otherwise.
	 */
	private boolean isNameFirstChar(char c) {
		//[5]    Name    ::=    (Letter | '_' | ':') (NameChar)* 
		
		if(Character.isLetter(c) ||  c == '_' || c == ':') {
			return true;
		}
		
		return false;
	}
	
	/**
	 * Read the conditional section from the data stream.
	 * 
	 * @return The conditional section.
	 */
	public DTDData readConditionalSect() {
	
		//Assumption:
		//	the first two characters of the conditional section have already been read
		//	So instead of getting <![INCLUDE ... we'll get [INCLUDE...
		/*
		[61] conditionalSect ::= includeSect | ignoreSect
	
		[62] includeSect ::= '<![' S? 'INCLUDE' S? '[' extSubsetDecl ']]>'
		[63] ignoreSect ::= '<![' S? 'IGNORE' S? '[' ignoreSectContents* ']]>'
	
		[31] extSubsetDecl ::= ( markupdecl | conditionalSect | PEReference | S )*
		[29] markupdecl ::= elementdecl | AttlistDecl | EntityDecl
		[45] elementdecl ::= '<!ELEMENT' S Name S contentspec S? '>'
		[52] AttlistDecl ::= '<!ATTLIST' S Name AttDef* S? '>'
		[70] EntityDecl ::= GEDecl | PEDecl
		[71] GEDecl ::= '<!ENTITY' S Name S EntityDef S? '>'
		[72] PEDecl ::= '<!ENTITY' S '%' S Name S PEDef S? '>'
		[69] PEReference ::= '%' Name ';' 
	
		[64] ignoreSectContents ::= Ignore ('<![' ignoreSectContents ']]>' Ignore)*
		[65] Ignore ::= Char* - (Char* ('<![' | ']]>') Char*)
	
			So the string to this method will look like:
			'[' ('INCLUDE' | 'IGNORE') S? '['
			('<!' char* )* '>' | S | conditionalSection | '%' char* ';')*
			']]>'
			
			conditionalSection := 
			'<![' ('INCLUDE' | 'IGNORE') S? '[' ('<!' char* '>')* ']]>'
		*/	
		
		String content = "";
		DTDData conditionalSect;
		char ch;
		int nesting = 1;
		
		while( !endOfData() ) {
			ch = getNextChar();
			if(ch == '<') {
				content += '<';
				if( lookNextChar() == '!' ) {
					content += '!';
					getNextChar();
					if( lookNextChar() == '[' ) { //nested conditional section
						content += '[';
						getNextChar(); //read the '['
						nesting++;
					}
				} // else throw DTDException
			}
			else if(ch == ']') {
				content += ']';
				if( lookNextChar() == ']' ) {
					content += ']';
					getNextChar();
					if( lookNextChar() == '>' ) { //nested conditional section
						content += '>';
						getNextChar();
						nesting--;
						if(nesting == 0) {
							break;
						}
					} // else throw DTDException
				} // else throw DTDException
			}
			else
				content += ch;
		}
	
		//CR: TODO: Throw DTDException if nesting != 0
		
		conditionalSect = new DTDData(content);
		
		return conditionalSect;
	}
	
	/**
	 * Reads the NmToken from the current location.
	 * If no valid nmToken is present, it returns
	 * <code>null</code>.
	 * 
	 * @return The NmToken read from the current 
	 * 		location; <code>null</code> if a valid
	 * 		NmToken is not present at the current
	 * 		location. 
	 */
	public String getNextNmToken() {
		/*
	[4]    NameChar    ::=    Letter | Digit | '.' | '-' | '_' | ':' | CombiningChar | Extender 
	[5]    Name    ::=    (Letter | '_' | ':') (NameChar)* 
	[6]    Names    ::=    Name (S Name)* 
	[7]    Nmtoken    ::=    (NameChar)+ 
	
	[84]    Letter    ::=    BaseChar | Ideographic 
	[85]    BaseChar    ::=    [#x0041-#x005A] | [#x0061-#x007A] | [#x00C0-#x00D6] | [#x00D8-#x00F6] | [#x00F8-#x00FF] | [#x0100-#x0131] | [#x0134-#x013E] | [#x0141-#x0148] | [#x014A-#x017E] | [#x0180-#x01C3] | [#x01CD-#x01F0] | [#x01F4-#x01F5] | [#x01FA-#x0217] | [#x0250-#x02A8] | [#x02BB-#x02C1] | #x0386 | [#x0388-#x038A] | #x038C | [#x038E-#x03A1] | [#x03A3-#x03CE] | [#x03D0-#x03D6] | #x03DA | #x03DC | #x03DE | #x03E0 | [#x03E2-#x03F3] | [#x0401-#x040C] | [#x040E-#x044F] | [#x0451-#x045C] | [#x045E-#x0481] | [#x0490-#x04C4] | [#x04C7-#x04C8] | [#x04CB-#x04CC] | [#x04D0-#x04EB] | [#x04EE-#x04F5] | [#x04F8-#x04F9] | [#x0531-#x0556] | #x0559 | [#x0561-#x0586] | [#x05D0-#x05EA] | [#x05F0-#x05F2] | [#x0621-#x063A] | [#x0641-#x064A] | [#x0671-#x06B7] | [#x06BA-#x06BE] | [#x06C0-#x06CE] | [#x06D0-#x06D3] | #x06D5 | [#x06E5-#x06E6] | [#x0905-#x0939] | #x093D | [#x0958-#x0961] | [#x0985-#x098C] | [#x098F-#x0990] | [#x0993-#x09A8] | [#x09AA-#x09B0] | #x09B2 | [#x09B6-#x09B9] | [#x09DC-#x09DD] | [#x09DF-#x09E1] | [#x09F0-#x09F1] | [#x0A05-#x0A0A] | [#x0A0F-#x0A10] | [#x0A13-#x0A28] | [#x0A2A-#x0A30] | [#x0A32-#x0A33] | [#x0A35-#x0A36] | [#x0A38-#x0A39] | [#x0A59-#x0A5C] | #x0A5E | [#x0A72-#x0A74] | [#x0A85-#x0A8B] | #x0A8D | [#x0A8F-#x0A91] | [#x0A93-#x0AA8] | [#x0AAA-#x0AB0] | [#x0AB2-#x0AB3] | [#x0AB5-#x0AB9] | #x0ABD | #x0AE0 | [#x0B05-#x0B0C] | [#x0B0F-#x0B10] | [#x0B13-#x0B28] | [#x0B2A-#x0B30] | [#x0B32-#x0B33] | [#x0B36-#x0B39] | #x0B3D | [#x0B5C-#x0B5D] | [#x0B5F-#x0B61] | [#x0B85-#x0B8A] | [#x0B8E-#x0B90] | [#x0B92-#x0B95] | [#x0B99-#x0B9A] | #x0B9C | [#x0B9E-#x0B9F] | [#x0BA3-#x0BA4] | [#x0BA8-#x0BAA] | [#x0BAE-#x0BB5] | [#x0BB7-#x0BB9] | [#x0C05-#x0C0C] | [#x0C0E-#x0C10] | [#x0C12-#x0C28] | [#x0C2A-#x0C33] | [#x0C35-#x0C39] | [#x0C60-#x0C61] | [#x0C85-#x0C8C] | [#x0C8E-#x0C90] | [#x0C92-#x0CA8] | [#x0CAA-#x0CB3] | [#x0CB5-#x0CB9] | #x0CDE | [#x0CE0-#x0CE1] | [#x0D05-#x0D0C] | [#x0D0E-#x0D10] | [#x0D12-#x0D28] | [#x0D2A-#x0D39] | [#x0D60-#x0D61] | [#x0E01-#x0E2E] | #x0E30 | [#x0E32-#x0E33] | [#x0E40-#x0E45] | [#x0E81-#x0E82] | #x0E84 | [#x0E87-#x0E88] | #x0E8A | #x0E8D | [#x0E94-#x0E97] | [#x0E99-#x0E9F] | [#x0EA1-#x0EA3] | #x0EA5 | #x0EA7 | [#x0EAA-#x0EAB] | [#x0EAD-#x0EAE] | #x0EB0 | [#x0EB2-#x0EB3] | #x0EBD | [#x0EC0-#x0EC4] | [#x0F40-#x0F47] | [#x0F49-#x0F69] | [#x10A0-#x10C5] | [#x10D0-#x10F6] | #x1100 | [#x1102-#x1103] | [#x1105-#x1107] | #x1109 | [#x110B-#x110C] | [#x110E-#x1112] | #x113C | #x113E | #x1140 | #x114C | #x114E | #x1150 | [#x1154-#x1155] | #x1159 | [#x115F-#x1161] | #x1163 | #x1165 | #x1167 | #x1169 | [#x116D-#x116E] | [#x1172-#x1173] | #x1175 | #x119E | #x11A8 | #x11AB | [#x11AE-#x11AF] | [#x11B7-#x11B8] | #x11BA | [#x11BC-#x11C2] | #x11EB | #x11F0 | #x11F9 | [#x1E00-#x1E9B] | [#x1EA0-#x1EF9] | [#x1F00-#x1F15] | [#x1F18-#x1F1D] | [#x1F20-#x1F45] | [#x1F48-#x1F4D] | [#x1F50-#x1F57] | #x1F59 | #x1F5B | #x1F5D | [#x1F5F-#x1F7D] | [#x1F80-#x1FB4] | [#x1FB6-#x1FBC] | #x1FBE | [#x1FC2-#x1FC4] | [#x1FC6-#x1FCC] | [#x1FD0-#x1FD3] | [#x1FD6-#x1FDB] | [#x1FE0-#x1FEC] | [#x1FF2-#x1FF4] | [#x1FF6-#x1FFC] | #x2126 | [#x212A-#x212B] | #x212E | [#x2180-#x2182] | [#x3041-#x3094] | [#x30A1-#x30FA] | [#x3105-#x312C] | [#xAC00-#xD7A3]  
	[86]    Ideographic    ::=    [#x4E00-#x9FA5] | #x3007 | [#x3021-#x3029]  
	[87]    CombiningChar    ::=    [#x0300-#x0345] | [#x0360-#x0361] | [#x0483-#x0486] | [#x0591-#x05A1] | [#x05A3-#x05B9] | [#x05BB-#x05BD] | #x05BF | [#x05C1-#x05C2] | #x05C4 | [#x064B-#x0652] | #x0670 | [#x06D6-#x06DC] | [#x06DD-#x06DF] | [#x06E0-#x06E4] | [#x06E7-#x06E8] | [#x06EA-#x06ED] | [#x0901-#x0903] | #x093C | [#x093E-#x094C] | #x094D | [#x0951-#x0954] | [#x0962-#x0963] | [#x0981-#x0983] | #x09BC | #x09BE | #x09BF | [#x09C0-#x09C4] | [#x09C7-#x09C8] | [#x09CB-#x09CD] | #x09D7 | [#x09E2-#x09E3] | #x0A02 | #x0A3C | #x0A3E | #x0A3F | [#x0A40-#x0A42] | [#x0A47-#x0A48] | [#x0A4B-#x0A4D] | [#x0A70-#x0A71] | [#x0A81-#x0A83] | #x0ABC | [#x0ABE-#x0AC5] | [#x0AC7-#x0AC9] | [#x0ACB-#x0ACD] | [#x0B01-#x0B03] | #x0B3C | [#x0B3E-#x0B43] | [#x0B47-#x0B48] | [#x0B4B-#x0B4D] | [#x0B56-#x0B57] | [#x0B82-#x0B83] | [#x0BBE-#x0BC2] | [#x0BC6-#x0BC8] | [#x0BCA-#x0BCD] | #x0BD7 | [#x0C01-#x0C03] | [#x0C3E-#x0C44] | [#x0C46-#x0C48] | [#x0C4A-#x0C4D] | [#x0C55-#x0C56] | [#x0C82-#x0C83] | [#x0CBE-#x0CC4] | [#x0CC6-#x0CC8] | [#x0CCA-#x0CCD] | [#x0CD5-#x0CD6] | [#x0D02-#x0D03] | [#x0D3E-#x0D43] | [#x0D46-#x0D48] | [#x0D4A-#x0D4D] | #x0D57 | #x0E31 | [#x0E34-#x0E3A] | [#x0E47-#x0E4E] | #x0EB1 | [#x0EB4-#x0EB9] | [#x0EBB-#x0EBC] | [#x0EC8-#x0ECD] | [#x0F18-#x0F19] | #x0F35 | #x0F37 | #x0F39 | #x0F3E | #x0F3F | [#x0F71-#x0F84] | [#x0F86-#x0F8B] | [#x0F90-#x0F95] | #x0F97 | [#x0F99-#x0FAD] | [#x0FB1-#x0FB7] | #x0FB9 | [#x20D0-#x20DC] | #x20E1 | [#x302A-#x302F] | #x3099 | #x309A  
	[88]    Digit    ::=    [#x0030-#x0039] | [#x0660-#x0669] | [#x06F0-#x06F9] | [#x0966-#x096F] | [#x09E6-#x09EF] | [#x0A66-#x0A6F] | [#x0AE6-#x0AEF] | [#x0B66-#x0B6F] | [#x0BE7-#x0BEF] | [#x0C66-#x0C6F] | [#x0CE6-#x0CEF] | [#x0D66-#x0D6F] | [#x0E50-#x0E59] | [#x0ED0-#x0ED9] | [#x0F20-#x0F29]  
	[89]    Extender    ::=    #x00B7 | #x02D0 | #x02D1 | #x0387 | #x0640 | #x0E46 | #x0EC6 | #x3005 | [#x3031-#x3035] | [#x309D-#x309E] | [#x30FC-#x30FE]  
		 */
		
		StringBuffer nmToken = new StringBuffer(""); 
		getNextNmToken(nmToken);
		
		if(nmToken.length() == 0) {
			return null;
		}
		
		return nmToken.toString();
	}
	
	/**
	 * Reads the NmToken at the current location
	 * and appends it to the StringBuffer. 
	 * 
	 * If there are no valid chars at the current
	 * location, then nothing is appended to the
	 * buffer.
	 * 
	 * @param buffer The StringBuffer to which all
	 * 			read chars are appended to.
	 */
	private void getNextNmToken(StringBuffer buffer) {
		
		char nextChar;
		
		while( !endOfData() ) {
			nextChar = lookNextChar();
			if(isNameChar(nextChar)) {
				buffer.append(nextChar);
					getNextChar(); //read it
			} else {
				break;
			}
		}
		return;
	}
	
	/**
	 * Reads the Name from the current location.
	 * If no valid Name is present, it returns
	 * <code>null</code>.
	 * 
	 * @return The Name read from the current 
	 * 		location; <code>null</code> if a valid
	 * 		Name is not present at the current
	 * 		location. 
	 */
	public String getNextName() {
		
		//[5]    Name    ::=    (Letter | '_' | ':') (NameChar)* 
		if(endOfData() || !isNameFirstChar(lookNextChar())) {
			return null; 
		}
		
		StringBuffer name = new StringBuffer("");
		
		name.append(getNextChar()); //append the first char
		getNextNmToken(name);
		
		return name.toString();
	}

	/**
	 * Performs checks to determine if the specified
	 * string conforms to the 'Name' construct.
	 * 
	 * @param name The string to be check.
	 * 
	 * @return <code>true</code> if the string conforms 
	 * 		to the 'Name' construct; <code>false</code>
	 * 		otherwise.
	 */
	public static boolean isName(String name) {
		
		char c = name.charAt(0);
		//CR: TODO: Use if(!isNameFirstChar)
		if( !(Character.isLetter(c) ||  c == '_' || c == ':')) {
			return false;
		}
		
		for(int i = 1; i < name.length(); i++) {
			c = name.charAt(i);
			//CR: TODO: Use if(!isNameChar(c))
			if(!(Character.isLetter(c) || Character.isDigit(c) ||
				c == '.' || c == '-' || c == '_' || c == ':')) {
				return false; 
			}
		}
		
		return true;
	}
	
	/**
	 * Reads Names, delimited by space chars,
	 * from the current location.
	 * If no valid Name is present, it returns
	 * <code>null</code>.
	 * 
	 * @return The Names read from the current 
	 * 		location; <code>null</code> if a valid
	 * 		Name is not present at the current
	 * 		location. 
	 */
	public String[] getNextNames() {
		
		ArrayList names = new ArrayList();
		//[6]    Names    ::=    Name (S Name)* 
		String name = getNextName();
		
		if(name == null) {
			return null;
		}
		names.add(name);
		
		while(name != null) {
			skipWhiteSpace();
			name = getNextName();
			names.add(name); 
		}
		
		return (String[]) names.toArray(new String[0]);
	}
	
	/**
	 * Reads NmTokens, delimited by space chars,
	 * from the current location.
	 * If no valid nmToken is present, it returns
	 * <code>null</code>.
	 * 
	 * @return The NmTokens read from the current 
	 * 		location; <code>null</code> if a valid
	 * 		NmToken is not present at the current
	 * 		location. 
	 */
	public String[] getNextNmTokens() {
		
		ArrayList nmTokens = new ArrayList();
		//[8]    Nmtokens    ::=    Nmtoken (S Nmtoken)*  
		String nmToken = getNextNmToken();
		
		if(nmToken == null) {
			return null;
		}
		nmTokens.add(nmToken);
		
		while(nmToken != null) {
			skipWhiteSpace();
			nmToken = getNextNmToken();
			nmTokens.add(nmToken); 
		}
		
		return (String[]) nmTokens.toArray(new String[0]);
	}
}
